Efforts to achieve dispersion of air delivered items on the ground have involved the use of parachutes, aerodynamic decelerators, autorotation, explosive ejection and other methods of imparting a lateral velocity component to the trajectory of the package after being dispensed. However, there are a large number of dispensers currently in use that only eject their packages downward. Method employed to achieve dispersion and prevent concentrations of the items into tight groups on the ground usually involve complex and expensive mechanisms that often have poor reliability.
An additional problem is that of landing an air delivered item in a safe or particular upward position. Cylindrically shaped bodies for example, are commonly employed in air delivered ordinance related items such as submunitions, mines, sensors, etc. It is often desired to have these items possess a preferred flight attitude, stable flight motion and a reduced terminal velocity. For example, if a cylindricaly shaped air delivered mine would fly in essentially a broadside attitude, without rotating about its longitudinal axis, it would always impact the ground on the same side of the mine body. This side of the mine could then be especially structurally reinforced more than the other sides to absorb the ground impact forces; the opposite side of the mine body could be considerably weaker. The combination of the broadside flight attitude and good flight stability would minimize oscillatory motion and would result in the mine coming to rest after ground impact with the relatively weaker side of the mine in an upward orientation. This will allow the warhead to function more effectively in an upward direction. A low terminal velocity will insure the mine structurally surviving ground impact and eliminating bouncing which could affect the final resting attitude.
In another area of concern, aerodynamic design is sought for falling and gliding munitions, which would enable the munition to scan the ground area by rotation of the munition as it descends, for detection of enemy targets on the ground. It is desired that a sensor on the munition be oriented to point towards the ground and not skyward, for such application. It is also desired for the sensor to rotate at an angle to the munition's vertical axis in flight, in order to scan the ground in ever-decreasing circles, as the munition rotates during descent thereby covering most of the ground area.